Rechargeable batteries used in remote transmitters of vehicle security systems currently have typically 1000 charge/discharge cycles before "end of life." Current methodologies allow for a certain level of discharge before the charging cycle begins. However, if the battery is removed from its charging fixture or field before it is fully charged, charging will not commence until that battery voltage drops below a voltage threshold.
U.S. Pat. No. 6,023,151 discloses a "smart" battery method and apparatus including a dynamic end of voltage (EODV) signal for recharging batteries, one that reflects environment, temperature, chemistry, or cycle and provides enhanced runtime and save-to-disk alarm.
U.S. Pat. No. 6,016,047 discloses a battery management system suitable for a "smart" battery including a processor and other means for recovery and producing signals based on temperature, and chemistry status.
U.S. Pat. No. 6,011,546 discloses a "smart" battery, part of a larger system, including provisions for self-monitoring and signals mobile processor battery charge state, readiness for re-use following charging, and modules user interface.
U.S. Pat. No. 5,870,685 discloses a system for monitoring battery capacity in a mobile station including a plurality of different thresholds which may trigger transmission of a signal for shutdown and recharging.
U.S. Pat. No. 5,754,029 discloses a battery charging apparatus including means for controlling battery charging current via calendars stored in PROM and uses specified event dates as well as a microprocessor for sending messages to an RF modulator.
U.S. Pat. No. 5,606,240 discloses a battery charger for a lithium battery including means for lengthening or shortening battery charging time based on a plurality of thresholds including protection, status, charge and time.
U.S. Pat. No. 5,572,110 discloses a "smart" battery charger including a memory for thresholds and parameters, means for automatically controlling the charging operation, and means for optimizing charging based on temperature, time, battery characteristics and requirements.
U.S. Patent No. 5,847,546 discloses a "smart" battery charging system including a memory and a microprocessor for programming charges and means for generating a charging signal that responds to charging status of the battery being charged.
U.S. Pat. No. 5,850,188 discloses an RKE diagnostic system including means for transmitting a plurality of signals regarding operations including charge status of battery and battery condition.
U.S. Pat. No. 5,717,387 discloses a vehicle control system including the ability to reprogram vehicle operation via transmitting signals such as low battery capable of controlling vehicle accessories.
U.S. Pat. No. 4,395,672 discloses an improved timer for a battery charger including an electric controller and includes a plurality of thresholds and parameters that extend charging cycle and to operate automatically.
Inductive (i.e. magnetic) coupling is a means of transferring electrical energy from one part (area) of a circuit to another part without requiring any ohmic (wire) connection. Instead, magnetic flux linkages couple two inductors (coils). The coils must be in close proximity in order to establish sufficient mutual inductance.